Given that the U.S. has the leading startup sector in the world, it seems likely that much of the fund's money would have found its way there regardless.

The OneWeb deal further complicates the picture. That money is coming directly from SoftBank rather than the fund, which is "still in the early planning stages," according to Softbank spokesman Matthew Nicholson.

Softbank had been in talks with the startup for "a long time," Nicholson said. He added that the Japanese conglomerate "was encouraged by recent conversations that Mr. Son had with President-elect Trump."

The investment in OneWeb will create about 3,000 jobs in the U.S. over the next four years, according to a statement from the companies.

Son has made savvy investments in the tech sector over the years, including Chinese e-commerce giant Alibaba(BABA). But he has struggled to make a success of a multibillion-dollar takeover of Sprint(S).

His attempt to merge the U.S. wireless carrier with rival T-Mobile(TMUS) in 2014 failed after it ran into regulatory hurdles. Son said this month he made the huge new investment pledge because Trump has made deregulation part of his platform.